1. Technical Field of the Invention
The present invention relates to a closing device comprising a flexible screen, such as an awning, whose lateral edges are guided in guide channels, thus allowing the screen to be moved between a closed position and an open position.
2. Prior Art
Some prior art closing devices have a flexible screen with a weighting bar extending over the whole width of the screen on a lower edge to allow the closing of the screen essentially under the weight of this weighting bar and to maintain it in a taut condition.
The presence of such a weighting bar has various disadvantages. Thus, a result of inertia, the speeds of opening and closing are limited and special precautions must be taken in order to brake the upward and downward motion of the screen in a sufficient amount of time before its stoppage. Furthermore, the weight of such a weighting bar necessitates a relatively large amount of energy to bring the screen into its open position. Finally, reliable safety means must be provided in the screen's control circuit in order to prevent accidents when a person or any object is below the screen during its descent towards the closed position.
Other prior art closing devices are provided with driving means having return-pulleys which pull on the lateral edges of the screen to bring the latter into its closed position. In such a closing device, it is not essential to provide a weighting and stiffening bar at the lower edge of the screen. From a practical point of view, however, such a stiffening and weighting bar is generally necessary to ensure the correct functioning of the closure.